1. Field of the Invention
This invention relates generally to machine tools and more particularly to controls for positioning a workpiece or working component of the machine tool.
2. Description of the Prior Art
Much has been done in the field of numerical control of machine tools. Some U.S. Pat. Nos. which have issued on this subject in the United States are as follows:
3,555,516 - Proctor PA1 3,573,737 - Rosenberg PA1 3,576,540 - Fair et al PA1 3,576,979 - McCall et al PA1 3,626,385 - Bouman PA1 3,634,661 - Fitzner PA1 3,634,662 - Slawson PA1 3,653,072 - Ballas et al PA1 3,668,653 - Fair et al PA1 3,720,814 - Klein PA1 3,720,817 - Dinwiddie PA1 3,725,651 - Cutler PA1 3,725,652 - Knovalina PA1 3,727,191 - McGee PA1 3,739,158 - Woodward PA1 3,746,845 - Henegar et al PA1 3,763,360 - Nishimura et al PA1 3,770,947 - Deily PA1 3,784,798 - Beadle et al PA1 3,812,474 - Linn et al PA1 3,827,030 - Seipp PA1 3,843,875 - Goodstal et al PA1 3,849,712 - Lankford et al PA1 3,670,153 - Rempert et al
In addition, there is now offered a hardwired solid-state controller for new milling machines by Cincinnati Milacron Company of Cincinnati, Ohio, where the control panel is pendant-mounted, as is a Cybelec (Swiss) back gauge control panel.
While several of the above patents and machines on the market employ controls with programs on cards or magnetic or paper tapes, the equipment required is often large and too expensive for economical adoption by the prospective customer. Furthermore, much of it, while available on new machine tools, is not adaptable to existing machine tools. Yet there are many machine tools throughout the world which could be greatly improved in utility if provided with economical numercial controls.
Several steps in this direction have been taken already and are represented by the U.S. Pat. of Gerald V. Roch, No. 3,618,349 for GAUGING SYSTEM FOR PRESSES issued Nov. 9, 1971. That patent describes manually pre-programmable front and rear gauging for press brakes and which could be readily retrofitted to existing press brakes. A more recent advancement is diclosed in the U.S. Pat. of Gerald V. Roch and Edward H. Sonn, No. 3,874,205 entitled DIGITALLY CONTROLLED MULTIPLE DEPTH STOP AND RETURN STROKE LIMIT CONTROL FOR PRESS BRAKES and issued Apr. 1, 1975. This can be retrofitted also to press brakes for pre-selecting various ram stroke depth and return stroke travel dimensions. There has remained a need for more options in such equipment at lower cost, and a more compact control panel readily movable in accordance with the wishes of the operator. The present invention is intended to answer at least some of these additional needs.